One of the great myths of NFL divisional play is that divisional games are more challenging than normal games. You hear announcers and pundits say it all the time. For example, It has often been said that the Jaguars play Indianapolis ‘tough’. The idea apparently being that because teams play in the same division twice a year, they are more familiar with one another, leading to unexpected results or closer than normal games.

Let’s examine if that is true for the Colts against the AFC South using the following criteria:

Wins and losses

Point differential

Percentage of close games

The AFC South was formed in 2002, giving us nine years of data. The teams have all played each other 18 times. For each matchup, I isolated out the 18 games the teams in question played against each other and compared them to the 126 other games the teams played in the regular season. There were no playoff matchups between the Colts and any AFC South foe in that span.

Jaguars vs Colts

Win Percentage Test

Jags record vs 30 other teams: 66-60 (.524)

Colts record vs 30 other teams: 96-30 (.762)

Colts vs Jags: 13-5 Indianapolis (.722 for Indy, .278 for Jags)

By this measure, the Jags have fared much worse against Indianapolis than a normal team. The Colts have fared almost exactly average. By winning percentage, you would expect the Colts to have won 13 or 14 games against the Jags. Considering that Jacksonville has won three games on 50+ yard field goals in that stretch, it’s safe to say, this number is right on. By winning percentage, you could say the Colts play the Jags tough, but the Jaguars are essentially an average opponent for the Colts.

Point Differential Test

Jags Points vs 30 other teams: 20.4-19.9

Colts Points vs 30 other teams: 27.2-19.7

Colts vs Jags: Colts 24.2 Jags 21.1

By this measure, the Jags play the Colts tougher than the average team. The Colts’ margin is smaller, and they score fewer points on offense and allow more on defense against the Jaguars than on average. The Colts offense is difficult for the Jaguars (as one would expect), but the Jaguars actually score 1.2 PPG more against Indy than against the average team. This would suggest that the Jaguars have built their offense to counteract the Colts defense. By this measure, the Jaguars certainly play the Colts ‘tough’.

Percentage of Close Games:

Percent of Jaguars games decided by 5 points or less against 30 other teams: 28.6%

Percent of Colts games decided by 5 points or less against 30 other teams: 29.4%

Percent of Colts/Jags games decided by 5 points or less: 44.4%

So there it is, the Colts and Jags are about 15% more likely to play a close game against each other than normal. Of course, the Jags and Colts already rank 2nd and 3rd in the NFL in 5 point or less games played over that span.

Verdict: It’s fair to say the Jaguars play the Colts tough. The Jags don’t win any more often than they should, but they keep it closer than one would think. They allow fewer points than average and score more than average. The two teams play close games more frequently than would be expected as well.

On the flip side, the Colts play the Jaguars tough. They win far more often than the normal Jaguars opponent, and score much more than the typical Jaguars opponent. In this instance, the myth is verified: Indy and Jacksonville play each other tough.

Titans Vs Colts

Win Percentage Test

Titans Record Vs 30 other teams: 72-54 (.571)

Colts Record vs 30 other teams: 96-30 (.762)

Colts vs Titans: 13-5 Indianapolis (.722 for Indy, .278 for Titans)

By this measure, the numbers are just as inconclusive as they were for the Jags/Colts. Again, the Colts should have expected to win 13.7 games given their normal win percentage. Considering they lost one game on a 60 yard field goal, perhaps that was all that kept the numbers from syncing up. From the Titans’ perspective, the Colts are a nightmare matchup. For the record, two times these two teams played in a meaningless game at the end of the regular season. They split the two matchups.

Point Differential Test

Titans Points vs 30 other teams: 22.6-21.6

Colts Points vs 30 other teams: 27.0-20.2

Colts vs Titans: Colts 25.6 Titans 17.3

The Colts actually had a better average margin of victory against the Titans than against an average team. The Titans held down the Indy offense slightly (although two games featured Peyton Manning for less than a quarter of game time). The Colts defense matches up quite well with the Titans offense, however, holding the Titans well below their average production. The Colts seem to be a much tougher matchup for the Titans than the Titans are for the Colts

Percentage of Close Games:

Percent of Titans games decided by 5 points or less against 30 other teams: 26.2%

Percent of Colts games decided by 5 points or less against 30 other teams: 31.0%

Percent of Colts/Titans games decided by 5 points or less: 33.3%

For a sample size this small, 2.3% is just about a rounding error. The Titans and Colts don’t play much closer to the vest than the Colts do against any other team.

Verdict:

The Titans don’t play the Colts tough. They play them pretty much average. There isn’t any real evidence they pose any great matchup advantage and the two teams are about as likely to play a close game as the Colts would on any given week.

Texans Vs Colts

Win Percentage Test

Texans Record Vs 30 other teams: 53-73 (.421)

Colts Record vs 30 other teams: 93-33 (.738)

Colts vs Texans: 16-2 Indianapolis (.888 for Indy, .111 for Texans)

The Colts own the Texans. Houston has never won even a single game in Indianapolis. The Texans haven’t been a good franchise for most of the existance of the AFC South, but the Colts domination of them has been more one sided than could be expected.

Point Differential Test

Texans Points vs 30 other teams: 19.7-22.8

Colts Points vs 30 other teams: 26.4-20.0

Colts vs Texans: Colts 30.1 Texans 19.3

Again, this is utter domination by Indy. The Colts are nearly four points a game better against Houston than against the average club. The defense is nearly a point a game better too. From a Houston perspective, the Texans offense plays a little worse against Indy, but their defense gives up a touchdown a game more than against the average team.

Percentage of Close Games:

Percent of Texans games decided by 5 points or less against 30 other teams: 26.2%

Percent of Colts games decided by 5 points or less against 30 other teams: 32.5%

Percent of Colts/Texans games decided by 5 points or less: 22.2%

Again, Indy and Houston are far less likely to play a close game against each other than either team is on a normal Sunday. These two teams only occasionally play tight games.

Verdict: Indy owns the Texans. There is no standard by which the Texans can be said to have played the Colts “tough” over the last nine years.

Conclusion:

There is no ‘division effect’ for the AFC South against the Colts. The Jaguars pose a more difficult matchup than normal, though the Colts still win at an expected rate. The Titans are basically exactly average, and the Texans have been an easier than average matchup for the Colts.

Since 2002, the Colts are 42-12 (.778) against the AFC South, and 67-23 (.744) against the rest of the NFL.

Since 2002, the Colts average 26.6 points against the South and 26.9 points against the rest of the NFL.

Since 2002 the Colts have allowed an average of 19.2 points against the South and 20.3 against the rest of the NFL.

Since 2002 the Colts have played close games 31.4% of the time against the South and 28.9% of the time against the NFL.